An instruction goes through 5 steps

• We assume that the instruction has been successfully fetched

• 1. Issue

  • The execution unit must be free (no structural hazard)
  • There should be no WAW hazard
  • If either of these conditions is false the instruction stalls. No further issue is allowed
    • There can be more fetches if there is an instruction fetch buffer (like there was in the CDC 6660)

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